*3.3. Influence of PLES Changing on ESDR*

#### 3.3.1. Influence of Production Space Changing on ESDR

There was a significant negative impact of production space on the ESDR for carbon sequestration service, soil conservation service, and water yield service during 2000–2018 (*p* < 0.01). The production space explained most of the variance in ESDR for carbon sequestration services, soil conservation services, and water production services, at 87%, 84%, and 48%, respectively (Figure 6a). For the carbon sequestration service, when the production space ratio exceeded 62.83%, the carbon sequestration service swas in deficit. Therefore, to ensure that the carbon sequestration service supply is greater than the demand, it is necessary to ensure that the ratio of production space is less than 62.83%. For the soil conservation service, the range was 0–98.73%. For the water yield service, there was no significant threshold effect due to the limited influence of production space (k = −0.02). Production space had a significant positive effect on the ESDR of grain production service and explained most of the variation in the ESDR for the grain supply service, at 89%. When the production space ratio exceeded 18.2%, grain production services supply exceeded the demand. In summary, it is necessary to ensure that the production space ratio in the study area is between 18.2% and 62.83% to ensure that all ecosystem services are in surplus.
